Banca de DEFESA: JOAO MARCOS FERREIRA DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JOAO MARCOS FERREIRA DOS SANTOS
DATE: 01/12/2021
TIME: 14:00
LOCAL: meet.google.com/qeg-bgft-duh
TITLE:

STUDY OF THE BEHAVIOR TO THE FLEXION OF PRODUCED ELEMENTS WITH FUNCTIONAL CRFA GRADATION

KEY WORDS:

Steel Fiber Reinforced Concrete, Functional Gradation by Layers, Elements Under Bending, Inductive Method

PAGES: 131
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Estruturas
SPECIALTY: Mecânica das Estruturas
SUMMARY:

Man's search for change linked progress to new ways of building and ways of conceiving structures, their materials, and methods. Faced with so many changes, concrete no longer presents itself as a simple mixture defined by the composition of aggregates, cement, and water, being today susceptible to the incorporation of new ones and the replacement of these basic materials by fibers, residues, and additives of various types. The incorporation of steel fibers, which resulted in the use of Steel Fiber Reinforced Concrete (SFRC) has shown great benefits to the conventional material in the world scenario, acting mainly in the post-cracking stage and mobilizing a portion of tensile strength triggered by the need of durability guarantee. In this context, the optimization of the use of short steel fibers in an element under bending, through a layered fiber grading, resulting in a functionally graded element (FGM), demonstrates its relevance. Fibers concentrated in higher percentages are located in the strip most stressed to traction and on the opposite compressed surface a null amount of these reinforcements is used. In this work, the elements have a cross-section graduated in 3 layers, for which the phase of determining the percentages of each fiber layer is highlighted, using the pre-existing results of SFRC beams in the three-point bending test (EN – 14651/2017) measured in previous works and comparing the height and area of cracks found in tests that correlate digital images and with displacement transducer measurements. It was possible to evaluate the influence of concrete casting through induction techniques and surface analysis. The results provide an effective overview of the preferential orientation of the fibers found in this configuration, 68° in relation to the oriented axis of the load application direction and 49° in relation to the plane perpendicular to the load application, confirmation of the initially desired proportion and expressive gains in post-peak crack containment, about 34.15%, when compared to beams in traditional molding, consequently, more effectively influencing the post-cracking resistance, bending and economy of steel fibers in the less tensioned regions of beams and plates molded in SFRC, like beams and slabs under bending.

BANKING MEMBERS:
Presidente - 1121075 - ALINE DA SILVA RAMOS BARBOZA
Interna - 1582140 - KAROLINE ALVES DE MELO MORAES
Externa à Instituição - ALESSANDRA LORENZETTI DE CASTRO - USP